Steam the cauliflower for 8 minutes in a steamer or in boiling water, until soft when poked with a fork.
Transfer steamed cauliflower to a high-powered blender along with the rest of the sauce ingredients.
Blend until completely smooth. If necessary, add more broth to thin out the sauce to desired consistency.
Taste sauce for flavor and add more ghee and/or sea salt to taste. Set aside until ready to use.
Add all ingredients for the meatballs to a mixing bowl and use your hands to mix everything together until well-combined (note: you can also perform this step using a stand mixer with the paddle attachment).
Form meatballs 1.5 to 2 inches in diameter and place on a plate.
Heat 2 tablespoons avocado oil or cooking oil of choice in a large cast iron skillet over medium-high heat. Once hot, place the meatballs on the hot skillet, giving each one plenty of room (you’ll need to do this in 2 to 3 batches). Cook 2 minutes, flip to the other side and cook another 2 to 3 minutes, until browned on 2 sides. Transfer to a plate.
Wipe out the skillet, lower the heat to medium-low and add the sauce. Bring sauce to a gentle boil then add the meatballs and stir. Cover and cook until meatballs are cooked through, about 5 to 8 minutes. For more developed flavor, cook meatballs at a very gentle simmer over medium-low heat for 30 to 60 minutes, stirring occasionally.
*You can replace the stone ground mustard with 2 tsp Dijon mustard.